This sound comes from "The Best of Sadie Saxton", a series of short awkward comedy clips shared by creator Sadie Saxton that collect her funniest cringe moments. The "you're welcome" line is spoken by Jenna in one of those clips, delivered with a perfectly flat, self-satisfied tone that turned it into a reusable reaction sound. It spread through TikTok and meme edits where creators needed a quick sarcastic reply, and it stuck around because the delivery is so instantly recognizable as petty confidence.